Your search found 7 records
(Location: IWMI HQ Call no: e-copy only Record No: H042333)
(0.12 MB)
The inner delta of the River Niger receives runoff from both the River Niger and the River Bani (249 000 km2) and is divided into a northern part (15 000 km2) and a southern part (58 000 km2). The average input and output discharges are approximately 1490 and 900 m3 s1 (1955/1996), respectively. The annual average water loss is approximately 40% (24-48%). The losses are greater in the northern (10Ð5 km3) than in the southern delta (8Ð2 km3), but this situation was reversed in 1984. The correlation between the output and input discharges is high for the northern part of the delta, but very low for the southern part, where the change in flooded area is likely to be limited. The average flooded area, calculated using a method based on the hydrological balance, is estimated to be about 10 000 km2 (north) and 14 000 km2 (south), which is consistent with the estimates provided by the previous authors.
2 Ogilvie, A.; Mahe, G.; Ward, J.; Serpantie, G.; Lemoalle, J.; Morand, P.; Barbier, B.; Diop, A. T.; Caron, A.; Namarra, Regassa; Kaczan, D.; Lukasiewicz, A.; Paturel, J-E.; Lienou, G.; Clanet, J. C. 2010. Water, agriculture and poverty in the Niger River Basin. Water International, 35(5):594-622. (Special Issue on "Water, Food and Poverty in River Basins, Part 1" with contributions by IWMI authors). [doi: https://doi.org/ 10.1080/02508060.2010.515545]
(Location: IWMI HQ Call no: PER Record No: H043335)
(6.38 MB)
Livelihoods in the Niger River basin rely mainly on rainfed agriculture, except in the dry extreme north. Low yields and water productivity result from low inputs, short growing seasons, dry spells, and excessive water. The overlap of traditional and modern rules impedes secure access to water and investments in agriculture by generating uncertain land tenure. Improved agriculture and water management require technical, sociological, and regulatory changes to address the wider causes of poverty. Illiteracy and poor water quality, both correlated with high infant mortality, are pressing problems. Rapidly increasing population, climatic changes and dam construction contribute to rural vulnerability.
3 Mulligan, M.; Fisher, M.; Sharma, Bharat R.; Xu, Z. X.; Ringler, C.; Mahe, G.; Jarvis, A.; Ramirez, J.; Clanet, J.-C.; Ogilvie, A.; Ahmad, Mobin-ud-Din. 2011. The nature and impact of climate change in the Challenge Program on Water and Food (CPWF) basins. Water International, 36(1):96–124. (Special issue on "Water, food and poverty in river basins, Part 2: Cross-basin analysis and synthesis" with contributions by IWMI authors). [doi: https://doi.org/10.1080/02508060.2011.54340]
(Location: IWMI HQ Call no: PER Record No: H043689)
(1.47 MB)
In this article the authors assess the potential impacts of projected climate change on water, livelihoods and food security in the Basin Focal Project basins. The authors consider expected change within the context of recently observed climate variability in the basins to better understand the potential impact of expected change and the options available for adaptation. They use multi-global circulation model climate projections for the AR4 SRES A2a scenario, downscaled and extracted for each basin. They nd significant differences in the impacts (both positive and negative impacts) of climate change, between and within basins, but also nd large-scale uncertainty between climate models in the impact that is projected.
4 Ogilvie, A.; Mahe, G.; Ward, J.; Serpantie, G.; Lemoalle, J.; Morand, P.; Barbier, B.; Diop, A. T.; Caron, A.; Namara, Regassa; Kaczan, D.; Lukasiewicz, A.; Paturel, J.-E.; Lienou, G.; Clanet, J. C. 2012. Water, agriculture and poverty in the Niger River Basin. In Fisher, M.; Cook, Simon (Eds.). Water, food and poverty in river basins: defining the limits. London, UK: Routledge. pp.131-159.
(Location: IWMI HQ Call no: IWMI Record No: H044842)
(2.24 MB)
5 Mulligan, M.; Fisher, M.; Sharma, Bharat; Xu, Z. X.; Ringler, C.; Mahe, G.; Jarvis, A.; Ramirez, J.; Clanet, J.-C.; Ogilvie, A.; Ahmad, M. D. 2012. The nature and impact of climate change in the Challenge Program on Water and Food (CPWF) basins. In Fisher, M.; Cook, Simon (Eds.). Water, food and poverty in river basins: defining the limits. London, UK: Routledge. pp.334-362.
(Location: IWMI HQ Call no: IWMI Record No: H044850)
(2.13 MB)
6 Mulligan, M.; Cruz, L. L. S.; Pena-Arancibia, J.; Pandey, B.; Mahe, G.; Fisher, M. 2012. Water availability and use across the Challenge Program on Water and Food (CPWF) basins. In Fisher, M.; Cook, Simon (Eds.). Water, food and poverty in river basins: defining the limits. London, UK: Routledge. pp.255-279.
(Location: IWMI HQ Call no: IWMI Record No: H044847)
7 Ekolu, J.; Dieppois, B.; Sidibe, M.; Eden, J. M.; Tramblay, Y.; Villarini, G.; Pena-Angulo, D.; Mahe, G.; Paturel, J.-E.; Onyutha, C.; van de Wiel, M. 2022. Long-term variability in hydrological droughts and floods in Sub-Saharan Africa: new perspectives from a 65-year daily streamflow dataset. Journal of Hydrology, 613(Part A):128359. [doi: https://doi.org/10.1016/j.jhydrol.2022.128359]
(Location: IWMI HQ Call no: e-copy only Record No: H051399)
(13.30 MB) (13.3 MB)
Understanding hydrological variability is of crucial importance for water resource management in sub-Saharan Africa (SSA). While existing studies typically focus on individual river basins, and suffer from incomplete records, this study provides a new perspective of trends and variability in hydrological flood and drought characteristics (frequency, duration, and intensity) across the entire SSA. This is achieved by: i) creating a 65-year long, complete daily streamflow dataset consisting of over 600 gauging stations; ii) quantifying changes in flood and drought characteristics between 1950 and 2014; iii) evaluating how decadal variability influences historical trends. Results of daily streamflow reconstructions using random forests provide satisfactory performance over most of SSA, except for parts of southern Africa. Using change-point and trend analyses, we identify-three periods that characterise historical variations affecting hydrological extremes in western and central Africa, and some parts of southern Africa: i) the 1950s–60s and after the 1980s–90s, when floods (droughts) tend to be more (less) intense, more (less) frequent and more (less) persistent; and ii) the 1970s–80s, when floods (droughts) are less (more) intense, less (more) frequent and less (more) persistent. Finally, we reveal significant decadal variations in all flood and drought characteristics, which explain aperiodic increasing and decreasing trends. This stresses the importance of considering multiple time-periods when analysing recent trends, as previous assessments may have been unrepresentative of long-term changes.
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